Memory devices are typically provided as internal, semiconductor, integrated circuits in computers or other electronic devices. There are many different types of memory including random-access memory (RAM), read only memory (ROM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), phase change random access memory (PCRAM), and flash memory, among others.
Solid state memory devices are utilized as volatile and non-volatile memory for a wide range of electronic applications. Flash memory, which is just one type of solid state memory, typically uses a one-transistor memory cell that allows for high memory densities, high reliability, and low power consumption.
Solid state memory devices, including flash devices, can be combined together to form a solid state drive. A solid state drive can be used to replace hard disk drives as the main storage device for a computer, as the solid state drives can have advantages over hard drives in terms of performance, size, weight, ruggedness, operating temperature range, and power consumption. For example, flash solid state drives can have superior performance when compared to magnetic disk drives due to their lack of moving parts, which may ameliorate seek time, latency, and other electro-mechanical delays associated with magnetic disk drives.
A solid state drive is a data storage device that uses solid state memory to store persistent data. A solid state drive may include NAND flash non-volatile memory and/or DRAM volatile memory. Solid state drive manufacturers can use nonvolatile flash memory to create a drive that does not use an internal battery supply thus allowing the drive to be more versatile and compact. Solid state drives using flash memory, also known as flash drives, can use standard disk drive form factors (e.g., 1.8-inch, 2.5-inch, and 3.5-inch, among others).
For some storage applications, hard drives may be arranged in a redundant array, such as a redundant array of inexpensive disks, also referred to as a redundant array of independent disks (RAID). A RAID can refer to data storage systems that can divide and replicate data among multiple hard disk drives. Such arrangements, e.g., in servers, may be intended to prevent data loss in case a particular drive fails. However, this practice may involve a substantial investment in extra capacity that is not realized in system storage capacity. For example, in some storage applications, as little as 5-30% of a hard disk capacity is used for storage in order to increase performance by reducing seek times associated with the hard disk(s). Furthermore, hard drive failure rates may tend to increase as the drive ages. Solid state devices, conversely, may tend to fail early in life, if at all, and then operate correctly through the end of their expected service life.